﻿210 
  PROCEEDINGS 
  OF 
  THE 
  CALIFORNIA 
  

  

  to 
  Asbang-o 
  Land, 
  etc., 
  by 
  Paul 
  B. 
  Dii 
  Chaillii 
  ; 
  8vo, 
  New 
  York, 
  1866. 
  Smith- 
  

   sonian 
  Reports, 
  for 
  tlie 
  years 
  186G 
  an 
  J 
  1869. 
  Savage 
  Africa, 
  etc., 
  by 
  W. 
  

   Winwood 
  Rcade 
  ; 
  8vo, 
  New 
  York, 
  1864. 
  Arctic 
  Researches 
  and 
  Life 
  among 
  

   the 
  E-jquimaux, 
  etc., 
  in 
  the 
  years 
  1860-62, 
  by 
  Charles 
  Francis 
  Hall 
  ; 
  8vo, 
  New 
  

   York, 
  186.T. 
  Missionary 
  Travels 
  and 
  Researches 
  in 
  South 
  Africa, 
  etc., 
  by 
  

   David 
  Livingstone 
  ; 
  Bvo, 
  New 
  York, 
  1858 
  ; 
  all 
  of 
  the 
  above 
  presented 
  by 
  

   Benj. 
  P. 
  Avery. 
  A 
  set 
  of 
  the 
  Pacific 
  Railroad 
  Reports 
  was 
  presented 
  by 
  Col. 
  

   R. 
  S. 
  Williamson. 
  

  

  A 
  special 
  vote 
  of 
  thanks 
  was 
  tendered 
  to 
  Frederick 
  Castle, 
  Esq., 
  

   for 
  his 
  valuable 
  donation 
  of 
  two 
  suits 
  of 
  Japanese 
  Armor, 
  presented 
  

   at 
  the 
  last 
  meeting 
  through 
  Dr. 
  George 
  Hewston. 
  

  

  The 
  following 
  paper 
  was 
  read 
  by 
  Dr. 
  Blake 
  : 
  

  

  On 
  the 
  Puebla 
  Range 
  of 
  Mountains." 
  

  

  BY 
  JAMES 
  BLAKE, 
  M.D. 
  

  

  The 
  Puebla 
  range 
  of 
  mountains, 
  situate 
  in 
  the 
  northern 
  part 
  of 
  Humboldt 
  

   County, 
  Nevada, 
  extends 
  in 
  a 
  direction 
  nearly 
  north 
  and 
  south 
  for 
  a 
  distance 
  of 
  

   about 
  sixteen 
  miles. 
  It 
  is 
  formed 
  in 
  the 
  principal 
  part 
  of 
  its 
  extent 
  by 
  two 
  ridges, 
  

   separated 
  by 
  a 
  valley, 
  this 
  vajley 
  again 
  being 
  divided 
  into 
  three 
  smaller 
  valleys 
  

   by 
  means 
  of 
  divides 
  running 
  between 
  the 
  two 
  ridges. 
  The 
  waters 
  from 
  these 
  

   smaller 
  valleys 
  escape 
  by 
  ravines 
  cut 
  through 
  the 
  eastern 
  ridge, 
  and 
  after 
  getting 
  

   into 
  Puebla 
  Valley, 
  run 
  north 
  to 
  join 
  the 
  waters 
  of 
  Trout 
  Creek. 
  The 
  eastern 
  

   ridge 
  is 
  formed 
  of 
  metamorphic 
  rocks, 
  principally 
  micaceous 
  and 
  talcose 
  schists, 
  

   with 
  some 
  metamorphic 
  limestones. 
  These 
  have 
  a 
  dip 
  of 
  about 
  78° 
  E., 
  with 
  a 
  

   strike 
  generally 
  north 
  16° 
  E. 
  They 
  appear 
  to 
  have 
  been 
  thrown 
  up 
  by 
  an 
  

   eruption 
  of 
  porphyry, 
  which 
  now 
  forms 
  the 
  crest 
  of 
  the 
  ridge. 
  The 
  western 
  

   ridge 
  has 
  the 
  shape 
  of 
  an 
  arc, 
  of 
  which 
  the 
  eastern 
  ridge 
  forms 
  the 
  chord. 
  It 
  

   overlaps 
  the 
  eastern 
  ridge 
  both 
  at 
  its 
  north 
  and 
  south 
  ends, 
  the 
  two 
  ridges 
  being 
  

   separated 
  in 
  the 
  middle 
  by 
  about 
  a 
  mile. 
  This 
  western 
  ridge 
  is 
  composed 
  en- 
  

   tirely 
  of 
  volcanic 
  rocks, 
  arranged 
  in 
  regular 
  strata, 
  with 
  a 
  dip 
  of 
  20° 
  to 
  the 
  

   west. 
  They 
  form 
  perfectly 
  conformable 
  layers, 
  and 
  extend 
  from 
  its 
  base 
  

   to 
  the 
  summit 
  of 
  the 
  ridge, 
  a 
  height 
  of 
  more 
  than 
  1,200 
  feet, 
  6,000 
  feet 
  

   above 
  the 
  level 
  of 
  the 
  sea. 
  The 
  beds 
  are 
  composed 
  of 
  many 
  varieties 
  of 
  

   volcanic 
  rock, 
  as 
  can 
  be 
  seen 
  by 
  the 
  specimens 
  I 
  have 
  brought 
  this 
  evening. 
  

   The 
  rocks 
  are 
  arranged 
  in 
  strata 
  of 
  from 
  2 
  or 
  3 
  feet 
  to 
  probably 
  100 
  

   feet 
  thick. 
  As 
  they 
  are 
  composed 
  of 
  materials 
  of 
  different 
  degrees 
  of 
  

   hardness, 
  some 
  of 
  the 
  rocks 
  weather 
  much 
  more 
  easily 
  than 
  others, 
  the 
  

   harder 
  strata 
  being 
  left, 
  forming 
  escarpments 
  in 
  some 
  instances 
  many 
  feet 
  

   in 
  height. 
  These 
  harder 
  strata 
  could 
  be 
  traced 
  projecting 
  along 
  the 
  side 
  of 
  

   the 
  mountain 
  as 
  far 
  as 
  the 
  eye 
  could 
  reach, 
  following 
  its 
  contour 
  with 
  perfect 
  

   regularity. 
  From 
  the 
  top 
  of 
  these 
  escarpments 
  the 
  surface 
  of 
  the 
  hill 
  always 
  

   fails 
  off 
  for 
  some 
  distance 
  conformably 
  to 
  the 
  dip 
  of 
  the 
  beds. 
  This 
  volcanic 
  

   ridge 
  attained 
  its 
  greatest 
  elevation 
  opposite 
  the 
  main 
  transverse 
  ridge 
  between 
  

  

  